title: "Theory of mind" is impaired in Huntington's disease.
abstract: BACKGROUND
  Huntington's disease (HD) is an autosomal dominant degenerative brain disorder that is characterized by motor, cognitive, and affective symptoms. There is, to some, degree, phenomenological overlap with schizophrenia. Schizophrenia patients are frequently impaired in "theory of mind" (ToM), that is, the ability to reflect on the mental states of self and others, with mixed evidence for a ToM deficit in HD.
  
  
  METHODS
  We examined ToM and neurocognitive functioning in 25 patients diagnosed with HD. For comparison, 25 patients with schizophrenia and 25 healthy controls, matched for age and gender, were included.
  
  
  RESULTS
  Patients with HD were impaired in ToM relative to controls. The pattern of neurocognitive deficits including ToM strikingly resembled the one found in schizophrenia, suggesting a selectively impaired ToM. In contrast to previous schizophrenia research, ToM was not associated with functional measures on the Unified Huntington's Disease Rating Scale (UHDRS).
  
  
  CONCLUSIONS
  The present study shows that patients with HD have deficits in ToM similar to schizophrenia. The association of impaired ToM with function needs to be established in future studies using rating scales that more specifically address interpersonal problems.
authors.affiliation: Research Department of Cognitive Neuropsychiatry and Psychiatric Preventive Medicine, LWL University Hospital, Ruhr-University Bochum, Bochum, Germany. martin.bruene@rub.de
authors.forename: Martin
authors.initials: M
authors.lastname: Brüne
authors.forename: Karina
authors.initials: K
authors.lastname: Blank
authors.forename: Henning
authors.initials: H
authors.lastname: Witthaus
authors.forename: Carsten
authors.initials: C
authors.lastname: Saft
mesh_terms: D000328:Adult; D000368:Aged; D003072:Cognition Disorders / Q000175:diagnosis / Q000209:etiology*; D004185:Disability Evaluation; D005260:Female; D006801:Humans; D006816:Huntington Disease / Q000150:complications* / Q000523:psychology*; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D012559:Schizophrenia / Q000150:complications; D012565:Schizophrenic Psychology; D056345:Theory of Mind / Q000502:physiology*